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    Hi,

    I was just wondering if the way I worked out this question is correct.

    Basically I subbed in 4 into the dT/dt equation and then the answer I got from that I added it to -7. Is this correct ?

    Thanks
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    (Original post by Olive123)
    Hi,

    I was just wondering if the way I worked out this question is correct.

    Basically I subbed in 4 into the dT/dt equation and then the answer I got from that I added it to -7. Is this correct ?

    Thanks
    They are asking for the temperature at the end of 4 hours. Subbing 4 into  dT/dt will give you the rate at which the temperature is increasing with time.

    To get back to an equation involving the temperature, what would you do to the  dT/dt equation? A hint is in the spoiler.
    Spoiler:
    Show
    Hint: Try integrating the differential equation to form a linear equation involving T and t.
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    (Original post by Dapperblook22)
    They are asking for the temperature at the end of 4 hours. Subbing 4 into  dT/dt will give you the rate at which the temperature is increasing with time.

    To get back to an equation involving the temperature, what would you do to the  dT/dt equation? A hint is in the spoiler.
    Spoiler:
    Show
    Hint: Try integrating the differential equation to form a linear equation involving T and t.

    So after integrating should I sub in T=-7degrees to get the constant?

    Should I then use the temp equation I got from integrating and sub in t=4 to find the temp at the end of 4 hours ?
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    (Original post by Olive123)
    So after integrating should I sub in T=-7degrees to get the constant?

    Should I then use the temp equation I got from integrating and sub in t=4 to find the temp at the end of 4 hours ?
    Yes, you would sub in T = -7 and t = 0 (as the temperature is initally -7 degrees), and then use the equation you got from integrating.
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    (Original post by Dapperblook22)
    Yes, you would sub in T = -7 and t = 0 (as the temperature is initally -7 degrees), and then use the equation you got from integrating.
    Thanks a bunch
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    Forget the question! Look at the hyperbolas the pixels on your screen are making
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    (Original post by Sinfire)
    Forget the question! Look at the hyperbolas the pixels on your screen are making
    Nice observation ha
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    Yes as long as your units of time are correct. As T(t) is the form of the equation f(x) I.e. The function of x will produce a temperature which is proportional to e to the power of the time taken including any coefficients.
 
 
 
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